1. Technical Field
The present invention relates to a vibration gyro for detecting an angular velocity of a rotating object.
2. Related Art
Vibration gyros are used for camera shake detection in photographic devices, direction detection in car navigation systems, and so on. In recent years, such a demand prevails in various fields, and improvement in performance to detect an angular velocity and downsizing has been required.
Vibration gyros employ a vibration mode in which an excitation mode and a detection mode are at right angles to one another. For example, JP-A-8-35841 discloses a vibration gyro provided with piezoelectric elements for excitation and detection formed on a resonator made of a material generating a mechanical vibration and having a square shape in cross section. The vibration gyro enables the resonator to vibrate largely and to detect an angular velocity with high accuracy by using the piezoelectric elements.
However, the vibration gyro in related art requires large electrical power to excite the resonator by the piezoelectric element for excitation, causing large electricity consumption. Further, the vibration gyro in related art needs to have the piezoelectric elements formed on four faces of the resonator, thereby causing difficulty in a process of mounting the piezoelectric elements associated with miniaturization of the resonator and requiring a large number of man-hours.